1. Field of the Invention
The present invention relates to a method of terminating a fiber rope utilising a device of the type comprising a housing member having a generally frusto-conical bore in which an end portion of the rope can be wedgedly retained.
2. Description of the Related Art
It is known from GB 1 341 013 to terminate a fiber rope using a device of the abovementioned type. A conically shaped wedge member locates within the fruato-conical bore of the housing member to wedgedly trap fibers of the end portion of the rope within the bore of the housing member thus terminating the rope. The housing member includes a device for attaching it to an anchorage, for example.
It has been that with this method of terminating a rope; that there is a tendency for the fibers of the rope end portion to abrade. Abrasion of the fibers occurs mainly in the region where the fibers contact an apex part of the conically shaped wedge member, although abrasion may also occur at a narrow mouth part of the housing member through which the terminated rope extends. The abrasion of the rope fibers substantially reduces the breaking strength of the rope.
A method of overcoming this problem is suggested in GB 2 236 546 in which the fibers of the rope end portion are treated with a resin composition. The resin composition is employed to provide a lubricating effect on the fibers to reduce abrasion thereof around the apex part of the conically shaped wedge member. Despite this, the combination of tensile load exerted on the rope and the stress induced in the constituent fibers of the rope end portion by the crushing action of the wedge member results in tensile failure of the rope at a point generally in a region extending from around the apex part of the wedge member to the narrow mouth part of the housing member.
U.S. Pat. No. 4,184,784 discloses a method of terminating a raided fiber rope of small diameter. The rope has a diameter of approximately 1/10m.sup.th inch (0.25 cm) and is combined with a plurality of parallel sections of such rope to be terminated in a single collar having a tapered interior channel. The collar is passed over the ends of the plurality of ropes, and each rope has a short tapered section of rope of the same material inserted in its braided core as a a device of thickening its end. The thickened ends of the plurality of parallel rope sections are separated ("fuzzed") into their individual fibers and a tube having a tapered outer surface is located therebetween. The tube is drawn into the collar by a centering tool and tightly wedges the "fuzzed" parts, plus a significant part of the braided lengths of the ropes, between the tube and collar.
This method is applied to the termination of bundles of very small diameter braided fiber ropes in a single termination device, said terminated bundles of ropes being employed to keep tensile loads from conductors in underwater cables. This method is not suitable for terminating larger diameter fiber ropes because their structures are more resistant to the compression necessary to secure the rope ends between the collar and tube. It will be appreciated from the disclosure of U.S. Pat. No. 4,184,784 that the amount of surface contact between each rope end and the respective surfaces of the channel and tube is restricted.